Class MetaModel Consistency Between PUML and C++

[melodyoncode]

• Refactor:
  • Enum literals in serialized outputs are now numeric integers; explicit values are preserved and unspecified entries auto-sequence (starting from 0).
  • Const-qualified flag for member variables removed from serialized metadata; static flags remain.
  • Method modifier determination improved for more accurate modifier classification (static/virtual/abstract/override/constructor/destructor).
• Tests:
  Integration fixtures updated and a new test added to cover revised enum value sequencing and member-variable serialization.